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Monocacy River

Maryland Tributary

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The Monocacy is the third largest tributary of the Potomac, after the Shenendoah River and the Anacostia River. The river flows 58.5 miles starting in northern Maryland, and drains an area of 744 square miles, the largest Maryland tributary to the Potomac. In 1974, the river was designated as a Maryland Scenic River, but it suffers from a serious problem with runoff and sedimentation.

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Contact Information
Maryland Department of Natural Resources